Terpenes in Cannabis sativa – From plant genome to humans

•In this Review Article we highlight recent progress in research on terpene metabolites in cannabis.•This includes highlighting issues related to claims of medicinal properties of cannabis terpenes.•We also highlight issues related to so-called ‘strains’ and the need to establish properly genotyped cannabis varieties for research and use in the industry.•We highlight areas that require future research, including expanded genotyping and genetic transformation. Cannabis sativa (cannabis) produces a resin that is valued for its psychoactive and medicinal properties. Despite being the foundation of a multi-billion dollar global industry, scientific knowledge and research on cannabis is lagging behind compared to other high-value crops. This is largely due to legal restrictions that have prevented many researchers from studying cannabis, its products, and their effects in humans. Cannabis resin contains hundreds of different terpene and cannabinoid metabolites. Many of these metabolites have not been conclusively identified. Our understanding of the genomic and biosynthetic systems of these metabolites in cannabis, and the factors that affect their variability, is rudimentary. As a consequence, there is concern about lack of consistency with regard to the terpene and cannabinoid composition of different cannabis ‘strains’. Likewise, claims of some of the medicinal properties attributed to cannabis metabolites would benefit from thorough scientific validation.